A centrifuge is a device with a rapidly rotating container that applies centrifugal force to its contents, typically to separate materials of different densities. Centrifuges are used in many industries and contexts, perhaps most commonly in laboratories. Typically, laboratory centrifuges are large and expensive relative to the amount of material that may be processed. For example, a centrifuge that utilizes test tubes to process relatively small amounts of content (on the order of 10 to 50 milliliters) is typically available for hundreds of dollars, and can be suitable for countertop use (e.g., roughly one cubic foot in size and 10 kilograms in mass). Centrifuges capable of processing larger amounts of content (on the order of 1 to 3 liters) often utilize a design of fixed or swinging buckets, are available at significantly higher prices (in range of multiple thousands of dollars), and are not suitable for countertop use (as they are typically many cubic feet in size and have a mass of over 100 kilograms).
Centrifuges are also used in non-laboratory environments. For example, restaurants and bars use centrifuges to separate liquid suspensions, such as to clarify juices (by removing pulp or fruit solids), remove solids from nut milks, and to separate fats from solids in pureed foods. Centrifuges can be superior to traditional separation methods, such as filtering, in that separation can be achieved very quickly and without the use of filters that are prone to clogging. In some instances, centrifuges can produce results not obtainable by traditional separation methods. For example, it may be difficult or impossible to remove fats from some pureed foods (particularly vegetable-based purees) under traditional methods. Because of the improved ability of centrifuges to separate particulates from liquid, centrifuges can also reduce the need to use chemical or enzymatic aids in clarifying or separating liquids (though in some instances, superior results can be achieved by using chemical or enzymatic aids in addition to a centrifuge).
Use of centrifuges has enabled restaurants and bars to provide, on a commercial level, products that were previously not widely available. For example, centrifuges can enable bars to obtain clarified citrus juices, which can be directly carbonated into beverages (such as cocktails). Such direct carbonation does not typically produce adequate results when applied to non-clarified citrus juices, as the particulate matter of the juices provides nucleation sights for dissolved carbon dioxide, reducing the ability of a liquid to retain carbonation.
Laboratory centrifuges can be difficult or problematic to utilize outside a laboratory environment, and particularly bars or restaurants. While smaller countertop centrifuges are similar in size to many kitchen appliances, they process very small amounts of liquid, such that use in a commercial restaurant or bar is difficult. These small centrifuges also often utilize test tubes, which can be difficult to clean and prone to breakage, especially in busy kitchen environments. Larger centrifuges require much more significant investments in terms of money, space, and maintenance, and are thus not obtainable by many restaurants and bars. For both countertop and larger centrifuges, expertise may be required to operate the centrifuge to produce satisfactory results without damaging the device. For example, while a centrifuge may successfully separate liquids (or solids from liquids) during operation, careful harvesting of the desired product (e.g., liquid of a desired density or a separated solid) may be required to avoid re-combination with other portions. Further, most centrifuges require that different containers be loaded with equal weights of liquid, such that the machine remains balanced during spinning. Misuse of a centrifuge can damage the unit, and in some instances result in catastrophic failure. Such failures may be hazardous, particularly in the context of larger centrifuges where failure may result in a container exiting the unit at high speed. These difficulties have, until now, limited the adoption of centrifuges outside of laboratories.
The drawing showing certain embodiments can be semi-diagrammatic and not to scale and, particularly, some of the dimensions are for the clarity of presentation and are shown greatly exaggerated in the drawings.